Metabolic imaging with cardiac magnetic resonance spectroscopy
The only non invasive technique for the assessment of cardiac metabolism in patients that does not use radiation is magnetic resonance spectroscopy (MRS). By interrogating signals from phosphorus-31 and hydrogen-1, spectroscopy offers a wealth of metabolic information on the heart muscle. This review focuses on the two areas of greatest potential for MRS: heart failure and ischemic heart disease. MRS has demonstrated deranged cardiac energetics in patients with heart failure, and this is probably a major mechanism contributing to contractile dysfunction. In ischemic heart disease, altered energetics are a highly sensitive indicator of the presence of myocardial ischemia, offering the prospect of a non invasive biochemical stress test for the heart. Although major technical development is required for the future, cardiac MRS holds great potential for clinical application.